seeing (that)
conjunction uk/ˈsiː.ɪŋ ˌðət/ us/ˈsiː.ɪŋ ˌðət/ (informal seeing as); (not standard seeing as how)
既然;考虑到，鉴于
considering or accepting the fact that; as
We may as well go to the concert, seeing as we've already paid for the tickets. 既然我们已经买了票，最好还是去听音乐会吧。